Videotelephony allows users in different locations to communicate in real time through the exchange of audio-video signals. With the rapid improvements and popularity of the Internet, videotelephony has become widespread through the deployment of video-enabled mobile phones, plus videoconferencing and computer webcams which utilize Internet telephony. For instance, many conventional large-scale videoconferencing systems utilize Integrated Services Digital Network (ISDN) or Internet Protocol (IP) transmission modes due to the need to convey the very large amounts of data generated by the endpoint devices' cameras and microphones. Such systems are often used by many participants in several different locations, all of whom can be viewed by every participant at each location. More modest systems rely on the use of personal computers, web or television cameras, and/or mobile devices (e.g., cellular telephones or smart phones) having integrated video cameras.
Current videotelephony systems operate under the assumption that a user invites a defined group of people to join a group or session, which exists only as long as users continue to participate in the group.